Riser clamp



FIG. 1 is a top, right, front perspective view of a first embodiment of a riser clamp according to our design;

FIG. 2 is a top, left, rear perspective view thereof;

FIG. 3 is a bottom, left, front perspective view thereof;

FIG. 4 is a bottom, right, rear perspective view thereof;

FIG. 5 is a front view thereof;

FIG. 6 is a rear view thereof;

FIG. 7 is a right side view thereof;

FIG. 8 is a left side view thereof;

FIG. 9 is a top view thereof; and

FIG. 10 is a bottom view thereof.

FIG. 11 is a top, right, front perspective view of a second embodiment of the riser clamp according to our design;

FIG. 12 is a top, left, rear perspective view thereof;

FIG. 13 is a bottom, left, front perspective view thereof;

FIG. 14 is a bottom, right, rear perspective view thereof;

FIG. 15 is a front view thereof;

FIG. 16 is a rear view thereof;

FIG. 17 is a right side view thereof;

FIG. 18 is a left side view thereof;

FIG. 19 is a top view thereof; and,

FIG. 20 is a bottom view thereof.

The broken lines are for illustrative purposes only and form no part of the claimed design. 

CLAIM The ornamental design for a riser clamp, as shown and described. 